Casting process for incorporating shafts, journals, or the like



ug. Il, 1925. LSIQHB RAYM HAFTQ,

une 6, 192

JOURNALS Wfl.

Wye.

Patented Aug. ll, 1925.

UNITED STATES PATENT OFFICE.

WILLIBALD RAYM, 0F DE'U'Z, GERMAY".

CASTING PROCESS FOR INCORPORATING SHAFTS, JOURNALS, 0B. THE LIKE.

, Application lcd June 6,

to which it appertains to make and use the same, reference being had to ,the accompanying drawings, and to letters or figures of reference marked thereon, which form Aa part of this specification.

It is known to incorporate shafts iand journals with castings in a 4direct manner, by casting in order to secure them in-same. This, however, is only possible with small castings, since during the contraction' of the casting, the. incompressibility of the shaft present therein sets Vup casting stresses which, in the case of large work, leither cause the casting to burst` atonce, or may become dangerous during subsequent use.

The object of the'present invent-ion is to rovide a kprocess "whereby such shafts, Journals or other parts can be incorporated direct into even large castings by casting, without any casting stresses being set up in the casting in shrinkin In particular, also, very large rollers, with a cast-in shaft, can be made in this manner.

rlihe process consists in providing a cer-A tain free space, corresponding to the shrinkage of the casting around the shaft or the like to be incorporated with the casting. The dimensions of this space are calculated so that, as the casting shrinks it will still exert sufficient pressure on the shaft to hold the same securely Vin the casting. The space may be produced in various ways, either by surrounding the shaft, at a certain distance, with a tube of thin sheet iron or the like, which will give way under the pressure set up by the contraction; or the intervening space may be filled up with material of any kind, for example a metallic alloy or the like, which melts during the contraction and exudes laterally or is burnt out, or is eliminated in any other way during the contraction.

The accompanying drawing illustrates various methods of carrying out the process and in which- 1924. Serial No. 718,332.

I Fi ure 1 is a longitudinal section of a roll and lts shaft illustrating one way of con-- necting them.`

Fig. 2 is a like view`of another way, and Fig. 3 is a cross section illustrating a third mode. In the embodiment according to Fig. 1 a is the shaft to be incorporate by casting,

and b is the casting', in this case a large w roller.. In order to allow for the shrinkage of the casting, the shaft is surrounded, prior to the iron being poured round it, with a sheet metal shell c, which is held at a certain distance away from the shaft by rings d at top and bottom. 0n the iron .being then poured round, in a suitable vmould, in the shape of the roller b, the tube c at first causes a space to be left between the metal and the shaft. As the metal cools, it contracts and gradually presses the tube o firmly against the shaft the air in the intervening space being able to escape above and below. The said s ace is soA calculated .that the necessary shrin ing on pressure for holding the shaft firmly in the roller can still ,be exerted. In this way the largest castings can be provided with shafts, journals or other inset parts without any dangerous shrinkage stresses making their appearance during the contraction.

In the embodiment according to Fig. 2, the shaft a is surrounded by a metallic alloy .e, which `melts at a lower temperature than the metal of the casting; and as the shrinkage lpressure increases, this alloy exudes, above and below, valong the shaft a, so that, in this case a certain amount of the liquefied alloy, corresponding to the increasing contraction, is expelled.

Instead of a metallic alloy, use may be made of any other substance which melts,

burns or vaporizes under the heat of the cast metal.

Fig. 3 represents the cross section of` a shaft a to be incorporated by casting, which 100 is provided with peripheral grooves f. Such grooves may also be provided when a tube surrounding the shaft is used, as in Fig. 1 and also when a metallic alloy or other sub- "stance is used, according to Fig. 2. The 105 grooves afford the advantage of facilitating the escape to the air or the exudation of the metallic alloy under the shrinkage pressure'. Moreover, in this case, one is not so dependenton the actual temperature of the casting 110 metal and need not calculate the contraction more securely preventing the shaft from turning inside the casting.

By means of this process, the largest castings of any kind can be provided with castin parts without dangerous castlng stresses being produced. e y y 1 The groovesof the peripheryof the shaft lvmay also be arranged in spiral form, and if ..dcsired, several sets of such spiral grooves kof diierentiitch can be arranged one above also ybe provided Ainthe' shaft, for they sameA purpose. Cores,ft o be subsequently with another.. oles, channels or the like may drawn from the castin ma also be arranged on the shaft, soft at, a ter providing suitable bores in the shaft, the roller can be cooled from the inside, through the shaft.' Iclaim: 1. The method of casting about cold, solid cores, which comprises castingV a metal about the core in spaced relation thereto, thecasti ing and the core beingrigidly connected by the shrinkage of the cast metal.

2. The method ofcasting about cold solid cores,` which comprises surrounding the core with a metal tube, and casting around said tube a metal capable of breaking down the structure of said tube to provide shrinkage space for the casting.

3. The method of incorporating a cold, solid core with a casting,whieh comprises separating the core and casting, during the molding of thelatter around the core, a. distance corresponding to the shrinkage of the castinlg in cooling.

4. he metho of incorporating a cold solid `core with a casting,` which comprises forming between the coreand casting an int'ervening space of such size as will be taken up by the casting in shrinking.

5. The method of casting about cold solid cores, which comprises forming recesses in the periphery of the core, surrounding the peri hery with a tube and casting around the atter a metal capable of breaking down and forcing the tube into the recesses.

6, The method of casting about cold solid cores, which 'comprises vsurroundin the core with a metal tube rheld in space relation from the core, and casting a large body of metal around said tube in contact therewith, 'said metal. operating in shrinking to force the tube into contact with the core. Y

In testimony that lI- claimY the foregoing as my invention, I have signed my name this 20th day of May l924 .f

DIPL. ING;- WILLIBALD RAYM. 

